George is a grumpy steamroller whose interactions with engines generally lead to trouble. He is owned by the Sodor Island Council. George is a grumpy, bad-tempered and rude steamroller. He is no friend of the railway, often heard rebelling that "railways are no good" and that they should be pulled up and turned into roads. George is happiest when he is rolling, but enjoys causing bother for the engines across the island too. He is grouchy, disagreeable and his unpleasant attitude and stubborn nature are often the cause of chaos and disruption, an example being when he crashed into Sir Handel's train for calling him a "great clumsy road-hog". He also does not get along with many road vehicles, either, as he insulted Caroline after she broke down.

It was likely that George was given a second chance and was very important in helping the steam engines and diesel engines in repairing the runway at the Sodor Airport, so that the first aeroplane could land. This shows that even he has a good side in him.

Spotlight Car is a Sodor Rescue car with a moving spotlight.

Diesel 10, or simply Diesel, is an evil diesel engine with a semi-sentient, hydraulic claw, which he has named "Pinchy".

Diesel 10 is an evil, conniving, manipulative, bullying and raving diesel engine. He absolutely despises steam engines, would call them taunting names like "Puffball" and "Teapot" and is not above doing anything to get rid of them if possible. He is Sodor's strongest (but not quite largest) diesel, his power being enforced by his slightly malfunctioning claw, Pinchy. He can use this deftly, and is even able to use it to make a sculpture. Pinchy, though, seems to have a mind of its own, as it has been shown to "punch" Diesel 10 in the face from time to time, which he loathes. All engines, steam and diesel alike, fear or respect him.

Despite his brutality, some of his demeanour appears to have cooled, and his behaviour has apparently improved enough that the Fat Controller allowed him back to the Island of Sodor. He gets along enough with the other Sudrian diesels, but his efforts to help are often only when it suits his personal interest and he still harbour his scheming ways and anti-steam sentiments.

Oil and diesel tankers are used for transporting crude oil and diesel fuel.

The diesel fuel is used to power machinery that run on diesel. The diesel tankers are usually found at the Vicarstown Dieselworks.

Duncan is a grumpy Scottish narrow gauge engine who came to the Skarloey Railway as a spare engine after Peter Sam's accident with some slate trucks.

Duncan is a Scottish narrow gauge engine with rough manners and a strong temper, making him the least social of the Skarloey Railway fleet. He was prone to boisterously bouncing about, which became known as "rock 'n' roll", whenever the mood took him, which once led to wedging in the north mouth of Rheneas Tunnel (probably caused from keystones knocked down by his funnel) and derailing on a stretch of line near Cros-ny-Cuirn.

While Duncan means well, he often grumbles and complains, usually about not being polished or being over-worked and can be rude, rough, stubborn, and bad-tempered. This can easily be seen from his dislike for Christmas for some reason. He claims to be a plain engine who believes in plainly speaking, an approach that can cause him to make callous or belligerent remarks. Duncan can be a competitive engine too, particularly with James. He can be impulsive, even more so than Sir Handel, and make rash decisions which usually lead to his own downfall, (such as getting in arguments or short-lived feuds with Rusty). He is not always quick to apologise or realise the error of his ways. However, upon Skarloey recalling Rheneas' gallant act to get his passengers home, Duncan readily admitted he had the wrong attitude and tried hard to be a more useful, more social, respectable engine in the future. When Rusty helped him after his derailment near Cros-ny-Cuirn, he apologised to him and extended a wheel of friendship, proving he has gratitude.

In spite of his rough ways, Duncan can be a little misunderstood as he is focused, confident, resourceful, and has a big heart. He is always willing to lend a helping hand whenever he can and wants to be really useful.

Bill and Ben are tank engine twins belonging to the Sodor China Clay Company. They are young and cheeky and love playing jokes on the bigger engines, but are kept in order by Edward and BoCo. They work in the china clay works and at Brendam Docks, where they are kept busy shunting trucks.

In Thomas & Friends, they briefly worked at Ffarquhar Quarry, thus the task of keeping them in order fell upon Mavis.

Bill and Ben are Sodor's most mischievous saddle tank engine twins, who have great fun in teasing and playing jokes on other engines of the railway. The two have four wheels, a tiny chimney and dome and a small squat cab. They often work in the China Clay pits and quarries. Their loads of clay can be used for many things such as paper, paint and pottery. They take trucks for engines on the mainline and ships in the harbour and are regularly seen around Brendam Docks. They enjoy attention and love taking visitors and being photographed. They tend to work together, like most twins, but even this youthful pair can have their arguments among themselves and can squabble with one another - particularly about whose fault one of their follies was. They are highly prone to playing tricks and being cheeky. They have even teased Gordon on more than one occasion. Duck has called them "the bees" before, for being terrors when they start buzzing around. Edward and BoCo are the only engines who can really keep them in order enough to put a stop to their games and make them scamper along and behave. There is no real harm to them, but even Edward admits that they are maddening at times. Bill appears to be the quicker-witted leader, while Ben seems to be the follower of the pair.

Despite their cheeky and mischievous antics, if a dangerous event occurs, such as a rockslide, they are shown to be quick-witted and capable to act to rescue anyone in trouble. This was shown when they saved a group of workmen and Thomas from many rockslides. The two also usually try to keep their jokes from becoming harmful, and will show remorse if their cheeky antics go too far and like all engines on the North Western Railway, they want to be Really Useful.

Skarloey, a red narrow gauge saddle tank engine, is the oldest engine on the Skarloey Railway. Talyllyn, from the Talyllyn Railway, is his twin and Rheneas is his brother.

Skarloey is the sage of the Skarloey Railway and is an old, faithful little engine. Although once full of enthusiasm and his own ideas in his youth, Skarloey is now one of the oldest engines on the Island. He is a calm-natured, quaint and mature engine and may often try to guide or watch over less experienced narrow gauge engines in his firm but fair and friendly manner. He acts kindly to engines and passengers alike and always enjoys a gentle, smooth journey through the woods by the lakeside and stopping at all the gates and stiles he remembers so well.

From the seventh to twelfth seasons of the television series, Skarloey had an occasional habit of being scared, timid, and clumsy. However, he went back to his older and more mature persona while working at the Blue Mountain Quarry and the railway.

Salty is a diesel shunter who works at Brendam Docks. He occasionally works at Ffarquhar Quarry.

Unlike some diesels, Salty is easy-going, jolly, friendly and very practical. He also enjoys telling stories revolving around the sea and fantasy. His seafaring ways and nautical accent are sometimes ridiculed and teased by the other engines (though Percy and Thomas imitated his accent since they thought he was amazing), but his usefulness almost always helps the others overlook that. He can work with trucks like no other engine; this is due to his enjoyment of working to a musical rhythm like the trucks and it may also be due to his vast collection of sea shanties. He loves the sea so much that he pines for it when he is away from it for long periods of time. He was once afraid to travel by ocean due to his knowledge of sea tales, but he overcame that.

Bulgy is a double-decker bus with an ideological opposition to railways.

Bulgy was a very grumpy, formerly cold-hearted and cynical double-decker bus who firmly believed that roads are superior to railways and would occasionally lie to get himself out of trouble. After being restored, he saw the error of his ways and changed his attitude.

Nowadays, he means well and works hard, and while he still believes passengers should travel by road—if the chance comes, he is willing to take advantage of an engine's inability to take passengers, even if it means sabotaging them if he thinks he can get away with it. However, Sir Topham Hatt keeps a close watch on him and makes sure that he is on his best behaviour, gently reminding Bulgy about what happens when he is not. Bertie also serves to mediate his opposing personality.

According to the "Character Cube" bonus features of several US DVDs, Bulgy has no scruples and knows how to tell a lie when he is in a tight jam and is good friends with Diesel.

Fergus is a small railway traction engine, who works at the Sodor Cement Works.

Fergus knows the rulebook off by heart, and his catchphrase is "Do it right!" His insistence on doing everything absolutely according to the rules can annoy the other engines, but he is a decent engine at heart and will not hesitate to help others in trouble. He is also friendly to nearly everyone he meets.

Arthur is a large tank engine originating from the London, Midland and Scottish Railway. He runs the Norramby Branch Line.

Arthur is a big tank engine who has never been naughty in his life. He was highly esteemed for his "spotless record" before he arrived on Sodor, never having made a mess or a fuss and never having caused an accident. His main duties were to shunt trucks and haul goods trains. Arthur can be a bit naive however and after a jealous Thomas tricked Arthur into setting his standards too high with the trucks, his record did not stay as spotless as he had hoped. Arthur is very obedient, cautious, and well-behaved. He aims to please in his work and do everything as best he can. He now mainly runs the Fishing Route by the coastal village, a duty which Thomas was only all too grateful to be relieved from. Here, Arthur enjoys the sea air and the smell of the fish.

Annie and Clarabel are Thomas' faithful coaches, whom he loves dearly and would never dream of being separated from them.

Annie and Clarabel both have seating accommodation for carrying passengers; Clarabel also has a brake compartment for luggage and a guard. The two coaches are nearly always seen coupled together, with Annie usually facing Thomas and Clarabel facing backwards.

Annie and Clarabel are respectful to all of the engines, but most of all Gordon and Thomas, whilst they respect Daisy least of all for insulting them and Henrietta. They show a kind and caring side to everyone on the whole railway. However, despite their kindness and sweetness, when needed they can be stern, especially Annie. For instance, they scolded Thomas for teasing Gordon after his accident, although they are no saints themselves. Once when Daisy was rude to them, they naughtily tricked her into thinking there was something wrong with her which caused confusion and delay. When the Fat Controller found out he told them that two wrongs do not make a right and that he expected better from both of them. Annie and Clarabel are best friends, but like all friends, sometimes they fall out but always try to make things right in the end.

Although the two respect Gordon, both Annie and Clarabel do not tolerate his arrogance more than other engines and like others they seek to teach him a lesson, as Annie was shocked by Gordon's rude comments about Edward. Additionally, when Gordon begged Thomas to speed up on Gordon's Hill, Clarabel smiled smugly at the express engine both before and after he got stuck on the hill.